声强测量系统用双水听器的校准方法研究

Calibration of Bi-hydrophone Used in Acoustic Intensity Measurement System

利用双水听器组成声强探头进行声强测量是研究水下声源和结构振动声辐射特性的有效方法之一 .由于用互谱法计算声强时 ,采用有限差分代替导数 ,因此对双水听器的一致性要求很高 .在耦合腔中采用传递函数法进行双水听器接收复声压的一致性校准 ,并采用易地交换测量消除声场不均匀性的影响 .

Since the derivative operation is replaced with the limited differential one when calculating acoustic intensity of sources by using cross_spectrum, higher uniformity of the bi_hydrophone is needed. A transfer function method is used to calibrate the uniformity of the complex acoustic pressure sensitivity of the bi_hydrophone under the coupling cavity circumstances. And the influence of the uneven acoustic field upon the calibration is cancelled by the means of a reciprocal measurement technique. Experiment results show that the geometry average value of the output voltage transfer function obtained by exchanging the position of front hydrophone and the back one can be used to exactly measure the amplitude's and the phase's uniformity deviation of the bi_hydrophone.